Endoscopic submucosal dissection is an alternative modality of surgery in treatment of early gastric cancer (EGC). The size of EGC is not a limitation of endoscopic treatment, but there are few data on prosperity of endoscopic treatment of superficial spreading EGC. The aim of this study was to investigate the rate and risk factors of lymph node metastasis of superficial spreading EGC for establishing proper criteria of endoscopic treatment of superficial spreading EGC.
Between 2000 and 2010, the patients who received curative surgery due to early gastric cancer in Severance Hospital, Seoul, Korea were enrolled. Superficial spreading EGC was defined as the largest lesion ≥6 cm.
Of 2758 EGC lesions, 105 (3.8%) lesions had a size of ≥6 cm, and 2653 (96.2%) lesions had a size of <6 cm.Superficial spreading EGC had higher rate of submucosal cancer 60.0% vs. 46.1%, P = 0.005) and lymphovascular invasion (25.7% vs. 12.7%, P < 0.0001) than <6 cm EGC. In the multivariable analysis, the odd ratio of tumor size (≥ 6 cm) was 1.28 (95% confidence interval, P = 0.388) for lymph node metastasis without statistical significance. In 105 patients with tumor size (≥ 6 cm), the rate of lymph node metastasis was higher in submucosal cancer than in mucosal cancer (25.4% vs. 7.1%, P = 0.017). The lymph node metastasis was significantly associated with lymphovascular invasion.
Superficial spreading EGC was not associated with an increased risk of lymph node metastasis as compared to EGC <6 cm.This finding suggests that superficial spreading EGC become a candidate of endoscopic treatment as EGC with smaller size.
Clinical trial identification
All authors have declared no conflicts of interest.